The inner ranks of the formation lifted their shields, rank by rank, from the front, and behind the shields the century became a crowded world of gloom, panted breath, the smell of sweat and muttered prayers to the gods. The muffled sounds from beyond were suddenly drowned out by the loud rattle of slingshot striking home, battering the leather surface of the shields. Cato lowered his head so that he was just able to see over the rim of his shield and raised his voice as he continued to intone the pace. ‘One! Two!’

There was a cry of pain as one of the auxiliaries was struck on the shin, the shot smashing the bone. He fell out of formation and covered his body with his shield as another man took his place. The bombardment intensified as they reached the line of stakes and Cato called the formation to a halt. He ordered two men to work the first of the stakes free. Another auxiliary was struck as a stone glanced off a shield and hit him in the face, breaking his cheek and blinding him in one eye. He let out a brief groan but kept his place.

‘Good lad,’ Cato called across to him.

The first stake came out and then another. And all the time slingshot, accompanied by rocks, smashed against the shields. Then there was a shout and the blare of a horn and Cato risked a look over his shield and saw enemy warriors clambering over the barricade and rushing forward to engage the auxiliaries.

‘Here they come! Brace yourselves!’

A moment later Cato felt his shield crash against him. He staggered back a pace before thrusting savagely forward and restoring the line at the front of the formation. More blows landed and hands tried to rip away the shield as the tribesmen attempted to get at their enemy. But the auxiliaries held their ground and punched their swords out, stabbing at the warriors surrounding them. The two men working the stakes continued their task, grunting as they wrenched them from the ground.

Suddenly there was a deafening crack and splinters shot through the confines behind the shields and a broad shaft of light pierced the gloom. Cato glanced round and saw that a huge Silurian warrior, stripped to a loincloth, his powerful body covered with swirling tattoos, was swinging a heavy war hammer back for another blow. His first had shattered the shield and caved in the chest of the man holding it. He now lay on the ground blinking as blood gurgled and sprayed from his lips. The hammer whirled round in a vicious arc and struck again, sending another man flying into his comrades.